Searches for SUSY in Events With Photons and Missing Transverse Momentum with the ATLAS Detector
In supersymmetric models with gauge-mediated supersymmetry breaking (GMSB), supersymmetry (SUSY) is broken in a hidden or secluded sector and is propagated to the visible sector by the standard gauge interactions. In R-parity conserving models, the lightest supersymmetric particle (LSP) is stable, which in GMSB models is the gravitino. In such models, supersymmetric particles are pair-produced and usually decay to the next-to-lightest supersymmetric particle (NLSP), which in turn decays to the NLSP’s SM partner particle and the gravitino.
Therefore, the type of NLSP, as well as its lifetime, determines the experimental signature. In this seminar, I will discuss searches for new physics at ATLAS involving photons and missing transverse momentum. The searches are motivated by the GMSB model described above, where the NLSP is a gaugino that decays promptly and is at least partially the photon’s partner particle. The gravitino escapes detection, resulting in missing transverse momentum. Nevertheless, the searches are primarily signature based, and we have set model-independent limits, as well as limits in a universal extra dimensions (UED) scenario. I will also discuss possible new directions for future searches.